Hi,
we have chosen the max17260 for our hardware design including a charger device and a 18650 LiFePO4 battery, allowing the system to run from 5V/USB-C (whilst charging) or from a battery.
Communication to the MAX17260 works well, battery voltage and current readings are ok and plausible - during charging mode as well as battery mode.
However, the results of the REPCAP, REPSOC, TTE and TTF readings are not making sense.
Our battery is a 1800mA LiFePO4, Vempty = 2.45V, Vcharge = 3.55V. Rsense = 10mOhm
After a POR or a software reset, the first reading appears to be mostly ok, e.g. for a fully charged battery in battery mode, it gives REPSOC 98%, REPCAP 1770mAh. TTE is not good though, i.e. 40min.
The next readings are, however, bad, jumping down to REPSOC 4%, REPCAP 88mAh and TTE 22min. The values do change over time, but still make no sense.
Initialisation is currently done according to EZ Config (following AppNote UG6595).
Everything I have tried, e.g. giving it time to charge or to run in battery mode, issuing a quick start, software reset, does not show improvement.
I assume the problem could lie within the initialisation and the calculations of the m5 algorithm. Is it actually possible to get the EZ Config to work properly with a LiFePO4?
We do not need the highest accuracy, but the values should be roughly ok and plausible.
Can anyone help? Is a custom config the only solution?
Is there a way to create our own custom config/initialisation or does anyone have a LiFePO4 config to share?
Grateful for any advice and feedback.